Question

How to insert a line into a file using sed before a pattern and after a line number? And how to use the same in shell script?

This inserts a line before every line with the pattern :

sed '/Sysadmin/i \ Linux Scripting' filename.txt

And this changes this using line number range :

sed '1,$ s/A/a/'

So now how to use these both (which I couldn’t) to insert a line into a file using sed before a pattern and after a line number or another approach?

Answer 1

You can either write a sed script file and use:

sed -f sed.script file1 ...

Or you can use (multiple) -e 'command' options:

sed -e '/SysAdmin/i\
Linux Scripting' -e '1,$s/A/a/' file1 ...

If you want to append something after a line, then:

sed -e '234a\
Text to insert after line 234' file1 ...